Correctly measuring the volume of a liquid Use a beaker to pour water into a 100 cm3
graduated cylinder until it is half full. Use the scale on
the side of the cylinder to measure the volume. Note: Your eye level must be exactly in line with the water level you are reading. The curve that the surface of the water makes in the graduated cylinder is called the meniscus. Always take the reading at the bottom of the meniscus.
Beaker Water Graduated cylinder Meniscus
Take reading at bottom of meniscus
Fig. 14 Correctly measuring the volume of a liquid.
3. Irregularly shaped objects, e.g. a stone or a potato: (a) Use a graduated cylinder. A graduated cylinder measures the volume of a liquid but it can also measure the volume of an object. Place the object in a graduated cylinder containing water and measure how much the water level rises. This is the same volume as the volume of the object. (See Fig. 15 below)
(b) Use an overflow can. If the object is too big to fit into a graduated cylinder, place it in an overflow can which is filled to the spout with water. The object pushes out a volume of water equal to its own volume. This water can then be measured using a graduated cylinder. (See Fig. 16)
Activity 1. To measure the volume of an irregularly shaped object using a graduated cylinder.
Equipment Beaker, graduated cylinder, stone, thread, water
Procedure 1. Using a beaker, pour some water into a graduated cylinder until it is half full.
2. Carefully read the level of water. 3. Tie the thread around the stone and gently lower it into the water until it sits at the bottom of the cylinder completely covered with water.
4. Carefully read the new level of water. 5. Subtract the first level from the second level to find the volume of the stone in cm3
